drooling nylon
drooling nylon
(OP)
why does nylon tend to drool? Is it do to crystallinity? Does an amorphous nylon drool less?
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RE: drooling nylon
Also nylon is hygroscopic, and if it has absorbed much water, then the outguessing as the water boils off will force some material out the nozzle as drool. If it is moisture causing the drool, the drool will spit and bubble with gas (steam) discharging from the melt.
Bottom line answer.
Ensure the granules are dry.
Ensure the nozzle heater is in good condition, is in good contact with the nozzle (good clean smooth mating surface).
Ensure the heater is very close to the tip of the nozzle.
Use a variable voltage controller to the nozzle, NOT AN ON OFF cycling type controller. DME controllers or even domestic light dimmer switches all work OK.
The temperature fluctuation during reaction times with on off type controllers is enough to cause drool then freeze then drool then freeze cycles to be set up.
Regards
pat pprimmer@acay.com.au
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RE: drooling nylon
RE: drooling nylon
RE: drooling nylon
I would ask how you are controlling your heat dissipation to the sprue. If you have to much contact from sprue to mold or not enough this can cause the sprue to freeze, drool and many other symptoms.
Some presses have the ability to vacuum the nozzle to prevent drool. I am not really clear on this, but can check with my molding floor to verify.
Cheers
Terry Ables
Micro Plastics Inc.
www.microplastics.com
RE: drooling nylon
Regards
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